358 



THE NATIONAL GEOGRAPHIC MAGAZINE 



RAT WITH CHARACTERISTIC SORE EYES, CAUSED BY A LACK IN ITS DIET OE THE 



"EAT SOLUBLE A" 



This rat shows the effects of a diet which lacked the unidentified essential, "fat soluble 

 A/' which is abundant in butter fat, but is not found in any of the oils or fats derived directly 

 from plants. It is present, however, in relatively small amounts in the green leaves of vege- 

 tables. Large amounts of green vegetables, therefore, particularly leafy vegetables, can be 

 made to take the place of butter fat to a certain extent. 



two others which are essential to health. 

 They are called respectively by research 

 men the "fat soluble A" and the "water 

 soluble B," 



The "fat soluble A" is present in the 

 fat of milk, the butter fat which forms 

 the cream and butter itself, but, curiously 

 enough, is not present in the vegetable 

 oils nor commonly in the cereals or foods 

 coming from the seeds of plants. It is, 

 however, a characteristic of green vege- 

 tables and is particularly abundant in the 

 green leaves of plants. 



The "water soluble B," on the other 

 hand, does occur in cereals, particularly 

 in their outer layers, and in green vege- 

 tables, as well as in a very large number 

 of other foods. 



The South Italian peasants build up 

 their strong, powerful bodies, then, from 

 the proteins and starches of their corn 

 polenta and from their green vegetables. 

 They get their fats from the olive oil, and 

 their "fat soluble A" is taken from the 

 greep vegetables. Their "water soluble 

 B" is obtained from both the corn and 

 vegetables, for it is present in both. 



The old doctrines of "strength-giving 



foods" must be analyzed from the new 

 standpoint of the presence of these two 

 newly discovered and not yet named sub- 

 stances, called by some the "fat soluble 

 unknown" — substances apparently as es- 

 sential to us as salt, but whose absence 

 unfortunately we cannot detect by taste 

 as we can the absence of salt. 



the analogy oe fresh vegetables and 

 eresh cereals 



It is plain, therefore, that we must 

 have vegetables ; the trouble is that we 

 like our vegetables fresh, and in the large 

 cities it is becoming very difficult to have 

 them really fresh at a reasonable price, 

 especially in winter. 



There was a time when we felt the same 

 way about our cereal foods. We wanted 

 them freshly ground every few days. 

 There are men living who remember 

 when we ate our corn-meal freshly 

 ground, taking a bag of corn to the little 

 mill and bringing back a bag of meal. 

 These people declare, and I have no 

 doubt they are correct, that there was a 

 flavor to this meal which our modern 

 milled product does not possess. 



